Smhi Weather Forcast Server

A Model Context Protocol (MCP) server that provides access to SMHI (Swedish Meteorological and Hydrological Institute) weather data, including forecasts and historical observations.

Disclaimer 😳

This project is the result of an experiment of using Claude Code AI plus Wispr Flow, where I mostly talk via Wispr to Claude, which then implements an MCP server connecting to the Swedish weather data service (SMHI). You can find my article (in Swedish) at this url https://www.ribomation.se/blog/2026/sa-har-kopplar-du-smhi-till-claude-ai/

The main objective is the journey, not the end result. That means, read the article, use Claude and follow along with the prompts and recreate your own weather service MCP.

Features

• 🌤️ Weather Forecasts - Get 10-day weather forecasts for any location in Sweden
• 📊 Historical Data - Access weather observations from 996+ SMHI stations
• 🏢 Station Listings - Browse available weather stations by parameter
• 📋 Parameter Catalog - List all 40+ available weather parameters

Installation

Prerequisites

• Node.js 18.0.0 or higher
• npm

Setup

1. Clone the repository:

git clone https://github.com/ribomation/smhi-weather-forecast-mcp-server.git
cd smhi-weather-forecast-mcp-server

2. Install dependencies:

npm install

3. Build the server:

npm run build

Usage

With Claude Desktop

Add this to your Claude Desktop configuration file:

MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "smhi-weather": {
      "command": "node",
      "args": [
        "/path/to/smhi-weather-forcast-mcp-server.js"
      ]
    }
  }
}

Then restart Claude Desktop.

With Other MCP Clients

The server uses stdio transport and can be integrated with any MCP client that supports stdio.

Available Tools

1. get-weather-forecast

Get weather forecast for a specific location.

Parameters:

• longitude (number, required): Longitude coordinate (-180 to 180)
• latitude (number, required): Latitude coordinate (-90 to 90)
• category (string, optional): Forecast category (default: "pmp3g")

Example:

{
  "longitude": 18.0686,
  "latitude": 59.3293
}

Returns: Complete forecast data for ~10 days with hourly weather parameters.

2. get-weather-observations

Get historical weather observations from a SMHI station.

Parameters:

• stationId (number, required): SMHI station ID
• parameterId (number, required): Parameter ID (see common parameters below)
• period (string, optional): Time period - one of:
  • "latest-hour" (default)
  • "latest-day"
  • "latest-months"
  • "corrected-archive"

Example:

{
  "stationId": 188790,
  "parameterId": 1,
  "period": "latest-hour"
}

Returns: Historical observation data with timestamps, values, and quality codes.

3. list-weather-stations

List available SMHI weather stations for a specific parameter.

Parameters:

• parameterId (number, required): Parameter ID to filter stations

Example:

{
  "parameterId": 1
}

Returns: List of stations with ID, name, coordinates, elevation, and active status.

4. list-weather-parameters

List all available weather parameters.

Parameters: None

Returns: Complete list of queryable weather parameters with IDs and descriptions.

Common Weather Parameters

Parameter	ID	Description
Temperature	1	Air temperature (°C)
Wind Direction	3	Wind direction (degrees)
Wind Speed	4	Wind speed (m/s)
Precipitation	5	Precipitation (mm)
Humidity	6	Relative humidity (%)
Snow Depth	8	Snow depth (cm)
Pressure	9	Air pressure (hPa)
Visibility	12	Visibility (km)

Development

Scripts

• npm run build - Build the project with tsup
• npm run dev - Run in development mode with watch
• npm run type-check - Type check without building
• npm start - Start the built server

Project Structure

src/
├── index.ts              # Entry point
├── server.ts             # MCP server setup
├── services/
│   ├── smhi-api.ts       # SMHI API client
│   ├── types.ts          # TypeScript types
│   └── test-api.ts       # API test script
└── (tools/, utils/ - for future expansion)

dist/                     # Build output (generated)

API Documentation

This server uses the SMHI Open Data API:

• Forecast API: https://opendata.smhi.se/apidocs/metfcst/
• Observations API: https://opendata.smhi.se/apidocs/metobs/
• Main Portal: https://opendata.smhi.se/

Important Notes

⚠️ API Changes: SMHI is modernizing their APIs during spring 2026. The current APIs used by this server may be deprecated. Monitor SMHI's updates page for changes.

Examples

Get Stockholm Weather Forecast

Ask Claude:

"What's the weather forecast for Stockholm?"

Claude will use get-weather-forecast with Stockholm's coordinates (18.0686, 59.3293).

Find Temperature Stations

Ask Claude:

"List all active temperature measurement stations in Sweden"

Claude will use list-weather-stations with parameterId: 1 (temperature).

Get Historical Data

Ask Claude:

"Show me the temperature readings from Abisko station for the last hour"

Claude will:

1. Use list-weather-stations to find Abisko's station ID
2. Use get-weather-observations to fetch the temperature data

License

MIT

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Built with Model Context Protocol by Anthropic.